i am confused, so you were running all those programs at once???.
What do you mean slow it down? going to 100%? well you cant really, thats just because the apps were requiring 100% cpu usage, sometimes i get 100% from aol, opera, avg antivirus, adaware se and disk keeper running at the same time, sometimes spyware can make the cpu go to 100% and not come back down.
Whats you full system specs?, place your system specs either in your signature, or in the my computer area located at the top of the forum on the blue bar. Maybe your cpu is a bad overclocker all Cpu's are not good at overclocking, either if the cpu is supposed to be a good overclocker, it doesen't mean that yours will be, its really luck, but if loads of people are reporting good overclocks with the cpu you have, then chances are you will be able to too, thats what i think anyway as my 3700+ was a cracking overclocker :p, you proberbly wont get to 4ghz, but depends what cpu it is, core 2 duo? then you have a chance i rekon.
How do you overclock? through the bios? Is your computer one your build from parts, or did you buy it in a package and pre built? if so, then that maybe why you cant overclock, with most pre build pc's overclocking is locked i belive.
Even if you did get it to 4ghz, were it maxes out at 100%, say running all those apps, it still will, the overclock will help mostly in gaming than normal apps like Microsoft Office & Internet browsing.
Will T